TriadES assists our clients with high resolution site characterization using a full tool box of cutting-edge tools to collect data at the locations and density necessary to meet project data quality objectives. The use of high resolution sampling and real-time analysis allows site investigators to efficiently address the largest uncertainty in environmental site characterization: sample representativeness due to subsurface heterogeneity. We pioneered the collection of high resolution geologic, hydrogeologic and contaminant data. TriadES has planned and executed cost-effective, high resolution site characterization projects that employ state-of-the-science tools such as:
- geophysical cone penetrometers,
- hydraulic proofing tools,
- membrane interface probe,
- ultra violet optical screening tool and
TriadES provides our clients with cost effective solutions for complex site characterization challenges, especially DNAPL sites that may have been under investigation for decades. We do this by providing high-density, real-time sample analyses and over 40 years of experience by our expert staff in site characterization.
Direct Sampling Ion Trap Mass Spectrometer (DSITMS) and EPA Method 8265
TriadES is the sole commercial vendor of Direct Sampling Ion Trap Mass Spectrometer (DSITMS) services under a license agreement from US DOE Oak Ridge National Laboratory. The DSITMS has been deployed at over 400 Federal, state and private facilities. The DSITMS provides real-time detection of volatile organic compounds (VOCs) in three minutes allowing the rapid in-field development of high resolution data sets.
The DSITMS is the basis for US EPA SW846 Method 8265. This method is very robust for the detection of VOCs in soil, groundwater and vapor samples. The method is capable of identification and quantification of petroleum related and chlorinated solvent VOC contaminants of concern from very low levels (single ppb) to high levels of contamination (100s-1000s ppm).
The use of EPA Method 8265 with dynamic work plans supports on-site decisions in Triad Approach site characterizations. The real-time quantification of VOC contaminants of concern allows the selection of sample locations to be made on a point by point basis, whether on a plan view (horizontal) or at a depth within a particular bore hole (vertical).
Furthermore, TriadES can provide accurate real-time and final conceptual site models of separate phase and dissolved plume contaminant distributions when the US EPA Method 8265 data are used in combination with three dimensional mapping and statistical analysis.
DSITMS Ideal for Complex Sites
Changing between discrete soil, groundwater, vapor, or MIP sample introduction methods to the DSITMS takes under 5 minutes. This means a single DSITMS instrument can be used as a very powerful MIP detector and moments later, as a stand-alone tool to analyze discrete soil or groundwater samples to quantify the MIP results. Down time is minimized, and the need to mobilize new analytical tools can be eliminated for Three-Phase Investigations.
No Down Time from High level Samples Overloading System
A unique feature of the DSITMS is that it is significantly less subject to cross contamination from high level samples than other techniques used for real-time data collection (i.e. GC/MS with EPA Method 8260). Decontamination of the DSITMS after a very high level sample (>1000 ppm) takes approximately 10 minutes, this includes running a blank analysis after decontamination to ensure the system has been properly cleaned. When a high level sample (>10 ppm) is run on a conventional instrument by EPA Method 8260, it can take 8-12 hrs to recover the system. The DSITMS ability to recover from high level sample analysis significantly reduces down time in the field, increasing sample through put and client cost saving.
Three Phase Investigation™
The rapid sample through put and the ability to also rapidly change between soil, groundwater and vapor analysis has allow TriadES to develop Three Phase Investigation™ for chlorinated solvent sites such as dry cleaners. The process allows investigation of separate phase source (soil), the associated groundwater plume (GW) and the potential for vapor intrusions (vapor) all in a single deployment with a single technology: the DSITMS and US EPA Method 8265.
DSITMS Advantages as a MIP Detector
The DSITMS is currently the only system available for the real-time direct speciation of VOC in the sample vapor stream produced by the GeoProbe MIP. The conventional detectors used with the MIP (FID, PID and ECD/XSD) provide only a gross indication of the total VOC contaminants of concern (FID and PID) with the ECD or XSD capable of providing an indication of the total chlorinated VOCs. The DSITMS provides real-time identification of the individual VOC contaminants as the vapor sample from the MIPis returned to the surface. The DSITMS distinguishes PCE, TCE, DCE and vinyl chloride from each other in real-time. Using conventional MIP detectors, the vapor must be collected and analyzed off line by gas chromatography to provide contaminant identification. TriadES is the sole commercial provider of the DSITMS and real-time direct speciation of VOC contaminants from the MIP.
Data Management and Communications
TriadES works with clients to ensure the data collected during high resolution site characterization are sufficient to meet the project data quality objectives. In order to do this, TriadES has developed procedures for data management and communications to easily allow real-time communications of data to both on-site and off-site client personnel. This is a critical aspect of cost effective high resolution site characterization project management to ensure efficient use of all available resources.
Contaminant Fate and Transport
TriadES has worked with GeoProbe to integrate the MIP with a geophycial cone sensor containing a piezocone. These sensors allow the simultaneous collection of VOC data along with soil type (stratigraphy) and subsurface pore pressure. These data are used together to rapidly delineate subsurface contaminant migration pathways. The VOC and geologic data collected with this system are used to construct and refine the CSM, in real-time. This CSM is used with site specific decision processes to further guide investigation during a particular deployment and to determine when the site has been adequately characterized.